As is well known, among combination weighing devices, there is a type of device in which articles discharged from a plurality of weighing hoppers selected by combination calculation are delivered to storage hoppers via a chute or the like, temporarily stored in these storage hoppers, and then discharged to a downwardly disposed packaging device and the like.
When this type of combination weighing device and packaging device are used, the opening and closing operation of the weighing hoppers and the packaging operation of the packaging device are performed at a predetermined time interval in order to adequately secure a gap between a batch of articles weighed first and a batch of articles weighed subsequently. A reduction in this time interval leads to acceleration of the process in the article weighing and packaging line. In order to achieve such effect, the articles need to be adequately delivered from the combination weighing device to the packaging device.
However, as described in Japanese Utility Model Laid-Open Publication No. 62-143601, depending on the state of the articles, there is a case where the articles bounce up and down the chute, causing a delay in the arrival of the articles, and by the time these articles arrive the storage hoppers, the storage hoppers are in an open state for the next batch. In this case, the articles are supplied, without being stored in the storage hoppers, to the packaging device at a timing different from the normal timing. This causes a packaging defect. Therefore, a device described in Japanese Utility Model Laid-Open Publication No. 62-143601 includes a second storage hopper disposed below a storage hopper (timing hopper). The opening and closing timing of the second storage hopper is delayed relative to the storage hopper. Then, the articles that have passed through without being stored in the storage hopper disposed above are temporarily stored in the second storage hopper and then discharged, and the operation timing of a packaging device is delayed accordingly. Thereby, the articles can be delivered to the packaging device in a favorable manner.
On the other hand, in view of the uselessness of the uniform opening and closing operation of a gate of a storage hopper (timing hopper) regardless of the characteristics and amount of articles, Japanese Patent No. 2681104 discloses a device in which the opening and closing speed and the opening degree of the gate of the storage hopper can be set in accordance with the type and amount of articles.
In addition, Japanese Patent Laid-Open Publication No. 11-292190 discloses a device that discharges articles from a storage hopper to a container. In this device, a replaceable insertion cylinder is disposed in the storage hopper (hopper for discharging articles) such that the articles can be adequately discharged into the container even when the shape and opening size of the container vary depending on the articles. The insertion cylinder has an opening whose size is in accordance with the opening size of the container, the characteristics and volume of the articles, and the like.
The articles are discharged by passing through the insertion cylinder.